Adapter and retainer assembly for nonrotary tool elements used with a rotary-hammer device



July 16, 1963 o. o. AMUNDsx-:N ETAL 3,097,858

ADAPTER AND RETAINER ASSEMBLY FOR NON-ROTARY ToorJ ELEMENTS USED WITH A ROTARY-HAMMER DEVICE Filed May 11, 1961 INVENTORS- Y, A l J United States Patent O 3,097,858 ADAPTER AND RETAINER ASSEMBLY FOR NON- ROTARY TL ELEMENTS USED WITH A ROTARY-HAMMER DEVICE Oiiver 0. Amundsen, Chicago, and Richard H. Kocian, Rolling Meadows, Ill., assignors to Skil Corporation, Chicago, Ill., a corporation of Delaware Filed May 11, 1961, Ser. No. 109,409 10 Claims. (Cl. 279-191) The present invention is directed to an adapter and retainer assembly for use with a rotary-hammer device and, more particularly, to an adapter which is readily attachable to the nose of a rotary-hammer device by a tool element retainer whereby to prevent rotation of a tool element mounted in the device and adapted for reciprocal hammering action only.

The present invention is a continuation-impart of application, Serial No. 33,141, -iled June 1, 1960, now U.S. Patent No. 2,990,187, dated June 27, 1961.

It is an important object of the present invention to provide a new and improved adapter and retainer assembly `for use with a rotary-hammer device whereby to prevent rotation of tool elements, such as chisels, mounted in the device for reciprocal hammering action only.

Another important object of the present invention is to provide a new and improved adapter and retainer assembly of the character described wherein the adapter is releasably attachable to the nose end of the rotaryhammer device by the retainer and wherein the adapter is slidably engageable with the shank portion of a tool element mounted in the rotary-hammer device in a manner permitting reciprocal hammer yactuation thereof while preventing rotation thereof.

Further objects of the invention are to provide a new and improved adapter and retainer assembly of the character described wherein the adapter and retainer may be easily and economically mass produced by means of conventional machine tools, wherein the adapter and retainer are rugged, and wherein the adapter may be easily mounted on the nose end of a rotary-hammer device and removed therefrom.

Certain other objects` of the invention will, in part, be obvious, and will in part appear hereinafter.

For a more complete understanding of the nature and scope fof the invention reference may now be had to the accompanying drawings wherein:

FIG. 1 is a side elevational view, partially in vertical section, of a rotary-hammer device having a one-piece cold chisel mounted therein for reciprocal hammer-like actuation only;

FIG. 2 is a vertical section taken generally on the line 2-2 of FIG. l;

FIG. 3 is a bottom plan View of the ytool retainer of FIG. 1;

FIG. 4 is a Ifront end view of the tool retainer;

FIG. 5 is a front end View of the adapter member of the assembly;

FIG. 6 is `a vertical section taken generally on the line 6 6 of FIG. 5 with a dust shield of the assembly being shown in broken lines; and

FIG. 7 is a vertical section taken through the nose portion of the rotary-hammer device of FIG. 1 with the adapter member of FIGS. 5 and 6 and the dust shield mounted thereon being retained against the nose member of the rotary-hammer device by the tool element retainer and with the adapter engaging the shank of the cold chisel in a manner whereby to prevent rotation thereof during reciprocal hammer-like actuation thereof.

As illustrated in lFIG. 1, a rotary-hammer device 10 "ice comprises a multi-part housing including a tubular portion 11, a first handgrip 12, and a second gripping handle 13 which projects normally from one side of the device 10. The rotary-hammer device 10 further includes an electric motor (not shown) which is adapted to be connected to a power source through a power cord 14. The electric ldrive motor circuit includes an on-and-ot switch which is controlled by a trigger-like member 15 associated with the handgrip 112.

The rotary-hammer device 10 is characterized by a cylinder 17 which is rotatably mounted within the tubular housing portion 11 and which is operably connected through a suitable gear train to the electric motor whereby Iduring actuation of the motor the cylinder 17 is rotated within the housing portion 11. As shown in FIG. 1, the forward end of the cylinder 17 is rotatably mounted in the forward end of the housing portion 111 by a suitable bearing 18. An axially bored drive member 19 having an internal hexagonal formation is threadedly secured in the lforward end of the cylinder 17 for rotation therewith and a smooth bored non-rotatable nose member 20 is secured to the forward end of the tubular housing portion 11. 'Ihe front end surface of the nose member 20 is provided with a pair of diametrically opposite longiltudinally extending bores 23, the purpose for which will be evident hereinafter.

Tool elements which are mounted in the device 10 for reciprocal hammer-like `actuation thereby are provided with long shank portions which project through the drive member 19` and into the cylinder 17 for impact engagement by a striker member 26 which is pneumatically reciprocated within the rotary cylinder 17. 'I'he striker member 216 is pneumatically reciprocated in the cylinder 17 as a result of reciprocation in the rear end of the cylinder 17 of a power piston (not shown) which is operably connected in a well-known manner to the electric motor. Suitable porting is provided in the cylinder 17 for the pneumatic actuation of the striker member 26. Rotary-hammer devices of this type are fully disclosed in co-pending applications, Serial No. 18,550, filed March 30, 1960, and Serial No. 19,784, tiled April 4, 1960.

Tool elements Vwhich are mounted in the rotary-hammer device 10 for rotary actuation thereby have shank portions provided with external Yhexagonal formations adapted for rotary driving engagement with the internal hexagonal formation of the ,drive member 19 whereby such t-ool elements are operably connected for rotation with the cylinder 17. Thus, a long shank tool element having an external hexagonal formation for slidable interengagement with the internal hexagonal formation of the drive member 19 may be provided with a combined rotary-hammering action due to the simultaneous rotation of the cylinder 17 and the reciprocal actuation therein of the striker member 26.

Tool elements which are mounted in the rotary-hammer device 10 for non-rotary reciprocal hammer `actuation thereby `are provided with rounded shank portions extending through the drive member 19 whereby such tool elements are not drivingly connected through the drive member 19 to the cylinder 17 for rotation therewith. Such a tool element, in the form of a cold-chisel 30, is illustrated in FIGS. 1 and 7. The one-piece cold chisel 30 is characterized by a body portion 31, a chisel formation 32 formed on one end thereof, and an integral shank portion including a rounded portion 33 which extends through the :drive member 19 and into the cylin-der 17 for limpact engagement by the striker member 26. A portion of the shank of the cold chisel 30 is enlarged and is provided with an external hexagonal formation 35 for a purpose which will be evident hereinafter. Forwarfdly of the enlarged hexagonally shaped portion 35,

the cold chisel 30 is provided with a reduced-in-diameter portion deiining an annular groove 36 which is adapted to be engaged by a tool element retainer to be described hereinafter whereby to` retain the cold chisel 30 in the rotary-hammer device 10 during reciprocal hammer-like actuation thereof.

The invention is primarily concerned with an adapter and retainer assembly for retaining and preventing rotation of a tool element, such as the cold chisel 30, mounted in the rotary-hammer device for hammer-like actuation only, which assembly, in the form illustrated in the drawings, includes an adapter member 37, a tool element retainer member 38, and a dust shield 39.

As best illustrated in FIGS. 1, 3, 4 and 7, the tool element retainer member 38, which is of a heat-treated steel wire construction, is pivotally or swingably mounted on the nose member 2t) for movement between a raised out-of-the-way position (not shown) and an operable tool element retaining position, as illustrated in FIGS. l and 7. The formed wire tool retainer 38 is characterized by a pair of generally parallel spaced arms 40 with the rear ends thereof being bent inwardly, as at 41, and with the forward ends thereof being bent in a manner ydefining two series of coils 42 and then being bent in a manner forming an open loop 43 disposed between the two series of coils 42 and serving to interconnect the pair of spaced arms 40 at the forward ends thereof.

The inwardly bent rear end portions 41 of the retainer 38 are rotatably received in a pair of `diametrically opposite radially extending bores 44 formed in the nose member whereby the retainer 38 is pivotally or swingably mounted on the nose member 20. As shown in the drawings, the radially extending bores 44 may be angularly located midway between the longitudinally extending bores 23 formed in the front end surface of the nose member 20. When the tool retainer 38 is swung downwardly from its raised, out-of-the-Way position into its operable tool element retaining position of FIGS. 1 and 7, the loop portion 43 thereof is positioned in embracing engagement in the annular -groove 36 formed on the cold chisel whereby to retain the same in the rotary-hammer device 10 during hammer-like reciprocation thereof.

The adapter member 37 of the assembly, as illustrated in FIGS. 5, 6 and 7, includes a generally at axially bored circular plate or disc member 46 having a diameter substantially equal to the diameter of the front end of the nose member 20. The disc member 46 is provided on each of its `faces with cent-rally located, axially bored hub-like projections 47 and 48. The rearmost hub-like projection 48 is adapted to -be inserted into the bore of the nose member 20 whereby it serves to position the adapter 37 relative to the nose member 20 with the bore thereof in axial alignment with the rotary axis of the rotary-hammer `device 10. Two rearwardly extending pins 49 are mounted in the disc member 46 in diametrically opposite relationship to each other and adjacent the outer periphery thereof. The adapter 37 is fitted against the nose member 20 so that the pins 49 will be received in the longitudinally extending bores 23 formed in the front end surface of the nose member 20. The pins 49 thus serve to prevent rotation of the adapter 37 relative to the nose member 20 and also aid in properly positioning the adapter 37 relative to the nose member 20.

The forward portion of the bore in the disc member 46 is provided with an internal hexagonal formation 52 which is adapted for slidable intertting engagement with the external hexagonal `formation on the cold chisel 30, whereby to permit reciprocal hammer-like actuation of the cold chisel 30 while preventing rotation thereof. With the rear hub-like projection 48 fitted in the bore of the nose member 20, the nose assembly of the rotary-hammer device 10 is strengthened whereby inadvertent use of the chisel 30 as a lever for a prying action will not be detrimental to the device 10.

The dust shield 39, which is preferably formed of a resilient material, is adapted to be fitted over the front surface of the adapter member 37 for obvious reasons. The dust shield 39 is axially bored whereby to accommodate passage of a tool element therethrough and in a manner whereby the dust shield 39 is axially bored whereby to accommodate passage of a tool element therethrough and in a manner whereby the dust shield 39 may be resiliently snapped over the forwardly extending hublike projection 47 for mounting thereof on the adapter 73, thus providing a forwardly facing resilient locking face 54 engageable by the two series lof coils 42 of the retainer 38. It is to be understood that the invention is not intended to be limited to an adapter-retainer -assembly having the dust shield 39` forming a part thereof. The resilient locking face 54 of the adapter member engageable by the retainer 38 and provided by the dust shield 39 in the `form of the invention illustrated in the drawings could be provided by a similarly shaped member formed of steel or other suitable material which does not serve asia dust shield but which is characterized by a resilient front face. Further, the adapter member could be formed with an integral forwardly directed resilient locking face -for engagement by the rear portions of the coils 42 of the retainer 38.

When it is desired to utilize the adapter member 37, ias when a tool element, such as the cold chisel 3G, is to be non-rotatably reciprocated with a hammer-like action by the device l0, the adapter member 37 is merely fitted against the front of the nose member 2G with the rear hub-like projection 48 inserted in the central bore of the nose member 2t) and with the pins 49 inserted in the bores 23 in the nose member 20, the retainer 38, of course, being positioned in its raised out-of-the-way position. The dust shield 39 or equivalent member is then resiliently snapped onto the forward hub-like projection 47 of the adapter 37, after which the chosen tool element is inserted into the device 10. The tool element retainer 38 is then swung downwardly into its operable position with the loop portion 43 thereof being disposed in embracing engagement in the annular groove 36 of the tool element. When the retainer 38 is in its operable position, the rearwardmost portions of the two series of coils 42 of the retainer 38 engage the resilient locking face 54 of the dust shield 39 whereby to retain the adapter 37 and the dust shield 39 attached thereto against the nose member 20 of the rotaryhammer device 10` during operation thereof. Obviously, if the adapter member is provided with ian integral resilient locking face, one step of the foregoing assembly operation will be eliminated. When it is desirable to insert a tool element adapted for rotary or combined rotary-hammering actuation in the rotary-hammer device i6, the adapter member 37 `may be readily removed from the nose member 20 when the retainer 38 is in its raised position during changing of the tool elements.

It will be understood that certain changes may be made in the construction or arnangement of the adapter `and retainer assembly disclosed herein without departing from tha spirit and scope of the invention as dened in the appended claims.

We claim:

l. An adapter and retainer assembly for the nose of a rotary-hammer device for preventing rotation of a tool element mounted in the device for hammer-like actuation only, said assembly comprising, an adapter member adapted to be disposed against the nose of the device and having means associated therewith adapted for engagement with a tool element mounted in the device in a manner preventing rotation of the tool element during hammer-like actuation thereof, and `a tool retainer separate from said adapter member mounted on the nose of the device with a portion thereof being adapted for retaining said adapter against the nose of the device.

2. An adapter and retainer assembly for the nose of a rotary-hammer device for preventing rotation of a tool element mounted in the device for hammer-like actuation only, said assembly comprising, an adapter member adapted to be disposed against the nose of the device and having means associated therewith adapted for engagement with a tool element mounted in the device in a manner preventing rotation of the tool element during hammerlike actuation thereof, and a formed wire tool retainer separate from said adapter member mounted on the nose of the device for swingable movement between out-of-theway and operable positions ad being characterized by coil portions adapted for retaining Isaid adapter against the nose of the idevice when said retainer is in its operable position.

3. An adapter `and retainer assembly for the nose of a rotary-hammer device for preventing rotation of a tool element mounted in the device for hammer-like actuation only, said assembly comprising, a centrally bored disc-like adapter adapted to be disposed against the nose of the device land having a rearwardly projecting hub-like projection adapted to be received in a tool-element-receiving bore in the nose of the device whereby to axially align the bore of said adapter with the Irotary axis of the device, said bore of said adapter having a configuration adapted for intertting slidable engagement with a tool element mounted in the device whereby to prevent rotation of the tool element during hammer-like actuation thereof, interiitting pin-and-recess means associated with said adapter and the nose of the device for preventing rotation of said adapter relative to the nose of the device, and a formed wire tool retainer separate from said disc-like adapter mounted on the nose of the device for `swingable movement between out-of-the-way and operable positions and being characterized by ycoil portions adapted for retaining said adapter against the nose of the device when said retainer is yin its operable position.

4. An adapter and retainer assembly for the nose of a rotary-hammer device for preventing rotation of la tool element mounted in the device for hammer-like actuation only, said assembly comprising, an adapter member adapted to be disposed against the nose of the device and having means associated therewith ladapted for engagement with a to-ol element mounted in the device in a manner preventing rotation of the tool element during hamer-like actuation thereof, a forwardly directed resilient locking face associated with said 'adapter member, and a tool retainer separate from said adapter member mounted on the nose of the device with a portion thereof being engageabile with said resilient locking face whereby to retain said adapter member against the nose of the device.

5. An adapter and retainer assembly for the nose of a rotary-hammer device for preventing rotation Iof a tool element mounted in the devi-ce for hammer-like actuation only, said assembly comprising, a centrally bored disc-like adapter adapted to be disposed against the nose of the device and adapted for engagement with a tool element mounted in the device in -a manner preventing rotation of the tool element during hammer-like actuation thereof, a forwardly directed resilient locking face associated with said adapter, and a formed wire tool retainer separate from :said disc-like adapter mounted on the nose of the device for swingable movement between out-of-theway land oper-able positions and being characterized by coil portions engageable with said resilient locking face associated with said adapter when the retainer is in its operable position whereby to retain said adapter against the nose of the device.

6. An adapter and retainer assembly for the nose of a rotary-hammer device for retaining and preventing rotation of a tool element mounted in the device Kfor harnmer-like actuation only, said assembly comprising, a centrally bored disc-like adapter adapted to be disposed against the nose of the device and adapted for engagement with a tool element mounted :in the device in a manner preventing rotation of the tool element during hammer-like actuation thereof, means for preventing rotation of said adapter relative to the nose of the device, said adapter having a forwardly directed resilient locking face associated therewith, and a formed wire tool retainer separate (from said disc-like adapter rnounted on the nose of the device for swingable movement between out-of-the-way and operable positions and being characterized by a loop portion engageable in a reduced neck portion of the tool element for retaining the same in the device during hammer-like actuation thereof and by coil portions engageable with said resilient locking face of said adapter whereby to retain said adapter against the nose of the device.

7. An adapter and retainer assembly for the nose of a rotary-hammer device dor preventing rotation of a tool element mounted in the device lfor hammer-like actuation only, said assembly comprising, a centrally bored disclike adapter adapted to be disposed against the nose of the device and having forwardly and rearwardly projecting hub-like projections with said rear hub-like projection being adapted to be received in a tool-elementreceiving bore in the nose of the device whereby to axially align the bore of the adapter with the rotary axis of the device, said adapter bore having a conguration adapted for interfitting slidable engagement with a tool element mounted in the device whereby to prevent rotation of the tool element during hammer-like actuation thereof, a centrally bored dust shield formed of resilient material fit-ted against the front end of said adapter and resiliently snapped over said `forward hub-like projection thereon, and a tool retainer separate from said disc-like adapter mounted on the nose of the device Ifor swingable Inovement between out-of-the-way and operable positions and having a portion adapted for engagement with the front surface of said dust shield when said retainer is in its operable position whereby to retain said dust shield and said adapter against thenose of the device.

8. An adapter and retainer assembly for the nose of a rotary-hammer device for retaining and preventing rotation of a tool element mounted in the device for hammer-like actuation only, said assembly comprising, a centrally bored disc-like adapter adapted to be disposed against the nose of the ldevice and having forwardly and rearwardly projecting hub-like projections with said rear hub-like projection being adapted to be received in a tool-element-receiving bore rin the nose of the device whereby to axially align the bore of the adapter with the rotary axis of the device, said adapter bore having a configuration adapted for interfitting slidable engagement with a tool element mounted in the device whereby to prevent rotation of the tool element during hammerlike actuation thereof, a pair of rearwardly projecting pins disposed adjacent the periphery of said adapter and adapted to be received in a pair of forwardly opening bores lformed in the nose of the device whereby to prevent rotation of said adapter relative to the nose of the device, a centrally bored dust shield formed of resilient material fitted against the front end of said adapter and resiliently snapped over said forward hub-like .projection thereon, and a Iformed wire tool retainer separate from said disc-like adapter mounted on the nose of the device for swingable movement between out-of-the-way and operable positions and being characterized by a loop portion engageable -in a reduced nec'k portion of the tool element for retaining the same in the device during hammer-like actuation thereof and by coil portions engageable with the front surface of said dust shield whereby to retain said dust shield and said adapter against the nose of the device.

9. For use with a rotary-hammer device having a cylinder rotatable in a housing, an axially bored drive member secured in the outer end of the cylinder, a striker member reciprocal in the rotatable cylinder for imparting a hammer-like action to tool elements mounted in the device and havin-g shank portions projecting through the drive member into the cylinder, power means for simultaneously rotating the cylinder and actuating the striker member, and a non-rotatable collar-like nose member secured to the outer end of the housing, the improvement comprising,`an axially bored plate-like adapter for use with the rotary-hammer device for preventing rotation of rounded shank tool elements mounted in the device for reciprocable hammer-like actuation only, said adapter being adapted to be titted against the end of the nose member, intertting pin-and-recess means associated with said adapter and with the nose member for preventing rotation of said adapter relative to the nose member, an internal formation in said axial bore of said adapter adapted for slidable, non-rotatable engagement with a similarly shaped external formation on the shank of a tool element mounted in the device whereby to -prevent rotation ofthe tool element during hammerlike recprocation thereof, and means mounted on the nose member and separate from the adapter for retaining same against the nose member.

10. For use with a rotary-hammer device having a cylinder rotatable in a housing, an axially bored drive member secured in the outer end of the cylinder, a striker member reciprocable in the rotatable cylinder yfor imparting a hammer-like action to tool elements mounted in the device and having shank portions projecting through the -drive member into the cylinder, power means for simultaneously rotating the cylinder and actuating the striker member, and a non-rotatable collar-like nose member secured to the outer end of the housing and having a pair of longitudinally extending bores formed in the outer end surface thereof, the improvement comprising, an axially bored plate-like adapter for use with the 'rotary-hammer device for preventing rotation of rounded `shank tool elements mounted in the device for reciprocable, hammer-like actuation only, said adapter being adapted to be tted against the outer end surface of the nose member, a pair of pins extending rearwardly from said adapter and adapted to be received in the pair of bores `formed in the outer end surface of the nose member whereby the bore of said adapter is axially aligned with the rotary axis of the rotary-hammer device and whereby to prevent rotation of said adapter relative to the nose member, means on said adapter adapted for slidable, non-rotatable engagement with a tool element mounted in the device whereby to prevent rotation of the tool element during hammer-like reciprocation thereof, and a tool element retainer separate from said platelike adapter swingably mounted on the nose member and having a portion thereof adapted for retaining said adapter against the nose member when said retainer is in its tool element-retaining-position.

References Cited in the tile of this patent UNITED STATES PATENTS 2,827,019 Taylor Mar. 18, 1958 2,936,736 Werstein May 17, 1960 2,990,187 Amundsen Iune 27, 1961 

1. AN ADAPTER AND RETAINER ASSEMBLY FOR THE NOSE OF A ROTARY-HAMMER DEVICE FOR PREVENTING ROTATION OF A TOOL ELEMENT MOUNTED IN THE DEVICE FOR HAMMER-LIKE ACTUATION ONLY, SAID ASSEMBLY COMPRISING, AN ADAPTER MEMBER ADAPTED TO BE DISPOSED AGAINST THE NOSE OF THE DEVICE AND HAVING MEANS ASSOCIATED THEREWITH ADAPTED FOR ENGAGE-EMENT WITH A TOOL ELEMENT MOUNTED IN THE DEVICE IN A MANNER PREVENTING ROTATION OF THE TOOL ELEMENT DURING HAMMER-LIKE ACTUATION THEREOF, AND A TOOL RETAINER SEPARATE FROM SAID ADAPTER MEMBER MOUNTED ON THE NOSE OF THE DEVICE WITH A PORTION BEING ADAPTED FOR RETAINING SAID ADAPTER AGAINST THE NOSE OF THE DEVICE, 